1. Field of the Invention
The present invention relates to a dispersion compensation module, and particularly to a polarization mode dispersion (PMD) compensation module that can provide a continuously variable compensation.
2. Description of Related Art
Optical communication systems are evolving from 10 Gbit/s systems to 40 Gbit/s systems to meet the demand for transmission capability. As the transmission speed of optical signals has increased, PMD has become one of the most important limiting factors for high-speed optical communication systems. Therefore, PMD compensation is a high priority concern in a high-speed optical communication system.
U.S. Pat. No. 5,822,100 discloses a PMD compensator which splits a received optical signal into two polarization states and which uses optical switching to add increments of delay to either polarization state of the signal. However, the delay of the PMD compensator is not continuously variable.
Therefore, an improved PMD compensation module is required to overcome the disadvantage of the prior art.